Back to square one = back to the very beginning of something (“de volta à estaca zero”)
After the earthquake many people in the city had to go back to square one and start rebuilding their lives again.
Depois do terremoto, muitas pessoas na cidade tiveram de voltar à estaca zero e reconstruir suas vidas.
Many scientists have to go back to square one when their experiments fail time and time again.
Muitos cientistas precisam voltar à estaca zero quando seus experimentos falham repetidas vezes.
José Roberto A. Igreja is the author and co-author of several ELT books, including:
A BRAND-NEW ELT BOOK!
600 Phrasal Verbs (with Jonathan T. Hogan)
Fluent Business English (with Robert C. Young)
English for Job Interviews (with Robert C. Young)
Fale Inglês como um Americano (with Robert C. Young)
American Idioms! (with Joe Bailey Noble III)